Haloalkanes and Haloarenes
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The Relative Rates of Thiol–Thioester Exchange and Hydrolysis for Alkyl and Aryl Thioalkanoates in Water
Orig Life Evol Biosph (2011) 41:399–412 DOI 10.1007/s11084-011-9243-4 PREBIOTIC CHEMISTRY The Relative Rates of Thiol–Thioester Exchange and Hydrolysis for Alkyl and Aryl Thioalkanoates in Water Paul J. Bracher & Phillip W. Snyder & Brooks R. Bohall & George M. Whitesides Received: 14 April 2011 /Accepted: 16 June 2011 / Published online: 5 July 2011 # Springer Science+Business Media B.V. 2011 Abstract This article reports rate constants for thiol–thioester exchange (kex), and for acid- mediated (ka), base-mediated (kb), and pH-independent (kw) hydrolysis of S-methyl thioacetate and S-phenyl 5-dimethylamino-5-oxo-thiopentanoate—model alkyl and aryl thioalkanoates, respectively—in water. Reactions such as thiol–thioester exchange or aminolysis could have generated molecular complexity on early Earth, but for thioesters to have played important roles in the origin of life, constructive reactions would have needed to compete effectively with hydrolysis under prebiotic conditions. Knowledge of the kinetics of competition between exchange and hydrolysis is also useful in the optimization of systems where exchange is used in applications such as self-assembly or reversible binding. For the alkyl thioester S-methyl thioacetate, which has been synthesized in −5 −1 −1 −1 −1 −1 simulated prebiotic hydrothermal vents, ka = 1.5×10 M s , kb = 1.6×10 M s , and −8 −1 kw = 3.6×10 s . At pH 7 and 23°C, the half-life for hydrolysis is 155 days. The second- order rate constant for thiol–thioester exchange between S-methyl thioacetate and 2- −1 −1 sulfonatoethanethiolate is kex = 1.7 M s . -
Chapter 7, Haloalkanes, Properties and Substitution Reactions of Haloalkanes Table of Contents 1
Chapter 7, Haloalkanes, Properties and Substitution Reactions of Haloalkanes Table of Contents 1. Alkyl Halides (Haloalkane) 2. Nucleophilic Substitution Reactions (SNX, X=1 or 2) 3. Nucleophiles (Acid-Base Chemistry, pka) 4. Leaving Groups (Acid-Base Chemistry, pka) 5. Kinetics of a Nucleophilic Substitution Reaction: An SN2 Reaction 6. A Mechanism for the SN2 Reaction 7. The Stereochemistry of SN2 Reactions 8. A Mechanism for the SN1 Reaction 9. Carbocations, SN1, E1 10. Stereochemistry of SN1 Reactions 11. Factors Affecting the Rates of SN1 and SN2 Reactions 12. --Eliminations, E1 and E2 13. E2 and E1 mechanisms and product predictions In this chapter we will consider: What groups can be replaced (i.e., substituted) or eliminated The various mechanisms by which such processes occur The conditions that can promote such reactions Alkyl Halides (Haloalkane) An alkyl halide has a halogen atom bonded to an sp3-hybridized (tetrahedral) carbon atom The carbon–chlorine and carbon– bromine bonds are polarized because the halogen is more electronegative than carbon The carbon-iodine bond do not have a per- manent dipole, the bond is easily polarizable Iodine is a good leaving group due to its polarizability, i.e. its ability to stabilize a charge due to its large atomic size Generally, a carbon-halogen bond is polar with a partial positive () charge on the carbon and partial negative () charge on the halogen C X X = Cl, Br, I Different Types of Organic Halides Alkyl halides (haloalkanes) sp3-hybridized Attached to Attached to Attached -
Title Several Reactions of Isocyanide and Related Compounds( Dissertation 全文 ) Author(S) Kobayashi, Shiro Citation
Several Reactions of Isocyanide and Related Compounds( Title Dissertation_全文 ) Author(s) Kobayashi, Shiro Citation 京都大学 Issue Date 1969-07-23 URL https://doi.org/10.14989/doctor.k916 Right Type Thesis or Dissertation Textversion author Kyoto University IN ISOCYANIDE AND COMPOUNDS 6 IR B s SEVERAL REACTIONS OF ISOCYANIDE AND RELATED COMPOUNDS 1 9 6 9 SHIRO KOBA Y ASHI PREFACE In the present thesis are collected the author's studies which have been carried out under the direction of Profossor Takeo Saegusa at Kyoto University during 1966 -- 1969. The studies include new organic reactions of isocyanide, carbon monoxide and carbene, which are characterized by a carbon atom carry ing lone-pair electrons. Reactions catalyzed by copper compounds as well as other Groups IB and IIB metal compounds constitute the central featl1re of tIl':' present studies. New organic reactions of isocyanidE' without catalysts are also presented. The author expresses his deep gratitude to Professor Takeo Saes'Usa for his constant guidance and encouragement throughout the work. Grateful acknowledgement is also made to Dr. Yoshihiko Ito for his valuable advice an? dis cussions during the course of studies. The author wishes to express his deep appreciation to Messrs. Kiwami Hirota, Nobuyuki Takeda, Toyoji Shimizu, Hiroshi Yoshioka, Yoshiharu Okumura. and Ikuo Morino for their active collaborations in carrying out the experiments. Shiro Kobayashi Department of Synthetic Chemistry Kyoto University March, 1969. (i) CON TEN TS Page INTRODUCTION ............................ .. 1 SYNOPSES .............................. .. 7 PART I. INSERTION REACTIONS OF ISOCYNJIDE CATALYZED BY COPPER COMPOUNDS 15 Chapter 1. Reaction of Isocyanide with Amine Catalyzed by Groups IB and IIB Metal Compounds, main ly by Copper Compounds. -
Classifying Halogenoalkanes Reactions Of
10 Halogenoalkanes H Naming Halogenoalkanes H H H H C H H H H Based on original alkane, with a prefix indicating halogen atom: H C C C H Fluoro for F; Chloro for Cl; Bromo for Br; Iodo for I. H C C C C H Br H H H Cl H H Substituents are listed alphabetically 1-bromopropane 2-chloro-2-methylbutane Classifying Halogenoalkanes Halogenoalkanes can be classified as primary, secondary or tertiary depending on the number of carbon atoms attached to the C-X functional group. H H H H H H H H C H H H H H C C C H H C C C H H C C C C H Br H H H Br H H Cl H H Primary halogenoalkane Secondary halogenoalkane Tertiary halogenoalkane One carbon attached to the Two carbons attached to the Three carbons attached to the carbon atom adjoining the carbon atom adjoining the carbon atom adjoining the halogen halogen halogen Reactions of Halogenoalkanes Halogenoalkanes undergo either substitution or elimination reactions Nucleophilic substitution reactions Substitution: swapping a halogen atom for another atom or groups of atoms - - Nucleophile: electron pair donator e.g. :OH , :NH3, CN :Nu represents any nucleophile – they The Mechanism: We draw (or outline) mechanisms to always have a lone pair and act as show in detail how a reaction proceeds electron pair donators Nu:- The nucleophiles The carbon has a small attack the positive H H H H positive charge because carbon atom of the electronegativity H C C X H C C + X- δ+ δ- Nu difference between the carbon and the halogen H H H H We use curly arrows in mechanisms (with A curly arrow will always two line heads) to show the movement of start from a of electrons or two electrons lone pair the centre of a bond The rate of these substitution reactions depends on the strength Bond enthalpy / of the C-X bond kJmol-1 The weaker the bond, the easier it is to break and the faster the reaction. -
UC San Diego UC San Diego Electronic Theses and Dissertations
UC San Diego UC San Diego Electronic Theses and Dissertations Title Isolation of Four-Coordinate Iridium(I) Monohydrides and the X-ray Crystal Structure of a Cobalt Tris-Isocyanide Alkane sigma-Complex / Permalink https://escholarship.org/uc/item/1b20p9sg Author Millard, Matthew David Publication Date 2013 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA, SAN DIEGO Isolation of Four-Coordinate Iridium(I) Monohydrides and the X-ray Crystal Structure of a Cobalt Tris-Isocyanide Alkane sigma-Complex A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Chemistry by Matthew David Millard Committee in charge: Professor Joshua S. Figueroa, Chair Professor Joseph M. O‘Connor Professor Nicholas C. Spitzer Professor F. Akif Tezcan Professor William C. Trogler 2013 Copyright Matthew David Millard, 2013 All rights reserved Ignature Page The dissertation of Matthew David Millard is approved, and it is acceptable in quality and form for publication on microfilm and electronically. Chair University of California, San Diego 2013 iii DEDICATION To my mother: for marrying the guy being chased by the cops while doing a wheelie on an orange motorbike up the street. iv EPIGRAPH Epig NEVER SAY NO TO A CHALLENGE Professor Karl O. Christe v TABLE OF CONTENTS Signature Page ......................................................................................................................... iii Dedication ............................................................................................................................... -
IODINE Its Properties and Technical Applications
IODINE Its Properties and Technical Applications CHILEAN IODINE EDUCATIONAL BUREAU, INC. 120 Broadway, New York 5, New York IODINE Its Properties and Technical Applications ¡¡iiHiüíiüüiütitittüHiiUitítHiiiittiíU CHILEAN IODINE EDUCATIONAL BUREAU, INC. 120 Broadway, New York 5, New York 1951 Copyright, 1951, by Chilean Iodine Educational Bureau, Inc. Printed in U.S.A. Contents Page Foreword v I—Chemistry of Iodine and Its Compounds 1 A Short History of Iodine 1 The Occurrence and Production of Iodine ....... 3 The Properties of Iodine 4 Solid Iodine 4 Liquid Iodine 5 Iodine Vapor and Gas 6 Chemical Properties 6 Inorganic Compounds of Iodine 8 Compounds of Electropositive Iodine 8 Compounds with Other Halogens 8 The Polyhalides 9 Hydrogen Iodide 1,0 Inorganic Iodides 10 Physical Properties 10 Chemical Properties 12 Complex Iodides .13 The Oxides of Iodine . 14 Iodic Acid and the Iodates 15 Periodic Acid and the Periodates 15 Reactions of Iodine and Its Inorganic Compounds With Organic Compounds 17 Iodine . 17 Iodine Halides 18 Hydrogen Iodide 19 Inorganic Iodides 19 Periodic and Iodic Acids 21 The Organic Iodo Compounds 22 Organic Compounds of Polyvalent Iodine 25 The lodoso Compounds 25 The Iodoxy Compounds 26 The Iodyl Compounds 26 The Iodonium Salts 27 Heterocyclic Iodine Compounds 30 Bibliography 31 II—Applications of Iodine and Its Compounds 35 Iodine in Organic Chemistry 35 Iodine and Its Compounds at Catalysts 35 Exchange Catalysis 35 Halogenation 38 Isomerization 38 Dehydration 39 III Page Acylation 41 Carbón Monoxide (and Nitric Oxide) Additions ... 42 Reactions with Oxygen 42 Homogeneous Pyrolysis 43 Iodine as an Inhibitor 44 Other Applications 44 Iodine and Its Compounds as Process Reagents ... -
Generic Functional Group Pattern in Ordero of Nomenclature Priority in Our Course. Specific Example Using Suffix (2D and 3D)
Generic Functional Group Pattern Specific Example Specific Example in ordero of nomenclature priority Using Suffix (2D and 3D) Using Prefix when in our course. when highest priority FG lower priority FG 1. carboxylic acid (2D) carboxylic acid (3D) O Condensed line formula IUPAC: ethanoic acid O H H prefix example C H common: acetic acid RCO2H or HO2CR C C R O #-carboxy H O RCH(CO H)R' H suffix: -oic acid 2 O not used in our course FG on FG on C H (acids are the highest priority prefix: #-carboxy the right the left H3C O group that we use) FG in the carbonyl resonance (2D) middle (C=O) is possible 2. anhydride (2D) Condensed line formula anhydride (3D) IUPAC: ethanoic propanoic anhydride O O RCO2COR' or ROCO2CR' H H O O H C C C CH C 3 R O R H3C O C H H 2 prefix example H O C H suffix: -oic -oic anhydride (2D) (just one -oic anhydride, O O O C C O if symmetrical) 3 1 H 4 H 2 prefix: #-acyloxyalkanecarbonyl O O OH (prefix not required for us) carbonyl resonance 4-acyloxymethanebutanoic acid (C=O) is possible (prefix not required for us - too difficult) 3. ester (2D) alkyl name (goes in front as separate word) ester (3D) H H H IUPAC: propyl ethanoate O C Condensed line formula C O C common: propyl acetate C R' H H R O RCO2R' or R'O2CR H H C C H O H H2 RCH(CO2CH3)R' prefix: alkyl suffix: -oate H C C CH3 O H C O C prefix example 3 H prefix: #-alkoxycarbonyl 2 O O (2D) 3 1 carbonyl resonance 4 2 (C=O) is possible O OH 4-methoxycarbonylbutanoic acid 4. -
(Mcrs) of the Last Decade
Molecules 2012, 17, 1074-1102; doi:10.3390/molecules17011074 OPEN ACCESS molecules ISSN 1420-3049 www.mdpi.com/journal/molecules Review Diversity Oriented Syntheses of Conventional Heterocycles by Smart Multi Component Reactions (MCRs) of the Last Decade Heiner Eckert Department Chemie, Technische Universität München, Lichtenbergstr. 4, Garching 85747, Germany; E-Mail: [email protected]; Tel.: +49-89-354-5532; Fax: +49-89-289-13329 Received: 9 December 2011; in revised form: 11 January 2012 / Accepted: 12 January 2012 / Published: 20 January 2012 Abstract: A collection of smart multicomponent reactions (MCRs) with continuative post condensation cyclizations (PCCs) is presented to construct conventional three- to seven- membered heterocyclic compounds in diversity oriented syntheses (DOS). These will provide a high degree of applying economical and ecological advantages as well as of practicability. Water, ionic liquids, and solvent-less syntheses as well as use of various forms of energy as microwave and ultrasonic irradiation are examined and discussed. Keywords: multicomponent reaction; MCR; MFCR; I-MCR; isocyanide; heterocycle; diversity oriented synthesis; solvent-less synthesis; alternative energy; microwave 1. Introduction Multi Component Reaction (MCR) chemistry [1,2] applied to the synthesis of heterocycles [3–5] with all its variations and extensions has undergone an enormous and meaningful upturn. Seeds sown in the last century, particularly appreciated by Ugi [6], have grown enormously and provided a plurality of novel reactions, new smart strategies as well as forward-looking methods, and high product diversity [7,8]. In this paper syntheses of conventional three to seven-membered heterocyclic structures (aziridine, azetidine, pyrrole, pyrrolidine, furan, indole, isoindoline, pyrazole, pyrazoline, imidazole, oxazolidine, thiazole, triazole, triazolidine, tetrazole, pyridine, pyrane, isoquinoline, pyrimidine, piperazine, oxazine, tetrazine, and oxadiazepine) are presented. -
Nomenclature of Carboxylic Acids • Select the Longest Carbon Chain Containing the Carboxyl Group
Chapter 5 Carboxylic Acids and Esters Carboxylic Acids • Carboxylic acids are weak organic acids which Chapter 5 contain the carboxyl group (RCO2H): Carboxylic Acids and Esters O C O H O RCOOH RCO2H Chapter Objectives: O condensed ways of • Learn to recognize the carboxylic acid, ester, and related functional groups. RCOH writing the carboxyl • Learn the IUPAC system for naming carboxylic acids and esters. group a carboxylic acid C H • Learn the important physical properties of the carboxylic acids and esters. • Learn the major chemical reaction of carboxylic acids and esters, and learn how to O predict the products of ester synthesis and hydrolysis reactions. the carboxyl group • Learn some of the important properties of condensation polymers, especially the polyesters. Mr. Kevin A. Boudreaux • The tart flavor of sour-tasting foods is often caused Angelo State University CHEM 2353 Fundamentals of Organic Chemistry by the presence of carboxylic acids. Organic and Biochemistry for Today (Seager & Slabaugh) www.angelo.edu/faculty/kboudrea 2 Nomenclature of Carboxylic Acids • Select the longest carbon chain containing the carboxyl group. The -e ending of the parent alkane name is replaced by the suffix -oic acid. • The carboxyl carbon is always numbered “1” but the number is not included in the name. • Name the substituents attached to the chain in the Nomenclature of usual way. • Aromatic carboxylic acids (i.e., with a CO2H Carboxylic Acids directly connected to a benzene ring) are named after the parent compound, benzoic acid. O C OH 3 -
Introduction to Alkenes and Alkynes in an Alkane, All Covalent Bonds
Introduction to Alkenes and Alkynes In an alkane, all covalent bonds between carbon were σ (σ bonds are defined as bonds where the electron density is symmetric about the internuclear axis) In an alkene, however, only three σ bonds are formed from the alkene carbon -the carbon thus adopts an sp2 hybridization Ethene (common name ethylene) has a molecular formula of CH2CH2 Each carbon is sp2 hybridized with a σ bond to two hydrogens and the other carbon Hybridized orbital allows stronger bonds due to more overlap H H C C H H Structure of Ethylene In addition to the σ framework of ethylene, each carbon has an atomic p orbital not used in hybridization The two p orbitals (each with one electron) overlap to form a π bond (p bonds are not symmetric about the internuclear axis) π bonds are not as strong as σ bonds (in ethylene, the σ bond is ~90 Kcal/mol and the π bond is ~66 Kcal/mol) Thus while σ bonds are stable and very few reactions occur with C-C bonds, π bonds are much more reactive and many reactions occur with C=C π bonds Nomenclature of Alkenes August Wilhelm Hofmann’s attempt for systematic hydrocarbon nomenclature (1866) Attempted to use a systematic name by naming all possible structures with 4 carbons Quartane a alkane C4H10 Quartyl C4H9 Quartene e alkene C4H8 Quartenyl C4H7 Quartine i alkine → alkyne C4H6 Quartinyl C4H5 Quartone o C4H4 Quartonyl C4H3 Quartune u C4H2 Quartunyl C4H1 Wanted to use Quart from the Latin for 4 – this method was not embraced and BUT has remained Used English order of vowels, however, to name the groups -
A Perovskite-Based Paper Microfluidic Sensor for Haloalkane Assays
ORIGINAL RESEARCH published: 26 April 2021 doi: 10.3389/fchem.2021.682006 A Perovskite-Based Paper Microfluidic Sensor for Haloalkane Assays Lili Xie 1, Jie Zan 1, Zhijian Yang 1, Qinxia Wu 1, Xiaofeng Chen 1, Xiangyu Ou 1, Caihou Lin 2*, Qiushui Chen 1,3* and Huanghao Yang 1,3* 1 Ministry of Education (MOE) Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, College of Chemistry, Fuzhou University, Fuzhou, China, 2 Department of Neurosurgery, Fujian Medical University Union Hospital, Fuzhou, China, 3 Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, China Detection of haloalkanes is of great industrial and scientific importance because some Edited by: haloalkanes are found serious biological and atmospheric issues. The development Jinyi Lin, of a flexible, wearable sensing device for haloalkane assays is highly desired. Here, Nanjing Tech University, China we develop a paper-based microfluidic sensor to achieve low-cost, high-throughput, Reviewed by: Xiaobao Xu, and convenient detection of haloalkanes using perovskite nanocrystals as a nanoprobe Nanjing University of Science and through anion exchanging. We demonstrate that the CsPbX3 (X = Cl, Br, or I) Technology, China nanocrystals are selectively and sensitively in response to haloalkanes (CH2Cl2, CH2Br2), Xuewen Wang, Northwestern Polytechnical and their concentrations can be determined as a function of photoluminescence University, China spectral shifts of perovskite nanocrystals. In particular, an addition of nucleophilic trialkyl *Correspondence: phosphines (TOP) or a UV-photon-induced electron transfer from CsPbX3 nanocrystals is Caihou Lin [email protected] responsible for achieving fast sensing of haloalkanes. -
Recent Advances on Mechanistic Studies on C–H Activation
Open Chem., 2018; 16: 1001–1058 Review Article Open Access Daniel Gallego*, Edwin A. Baquero Recent Advances on Mechanistic Studies on C–H Activation Catalyzed by Base Metals https:// doi.org/10.1515/chem-2018-0102 received March 26, 2018; accepted June 3, 2018. 1Introduction Abstract: During the last ten years, base metals have Application in organic synthesis of transition metal- become very attractive to the organometallic and catalytic catalyzed cross coupling reactions has been positioned community on activation of C-H bonds for their catalytic as one of the most important breakthroughs during the functionalization. In contrast to the statement that new millennia. The seminal works based on Pd–catalysts base metals differ on their mode of action most of the in the 70’s by Heck, Noyori and Suzuki set a new frontier manuscripts mistakenly rely on well-studied mechanisms between homogeneous catalysis and synthetic organic for precious metals while proposing plausible chemistry [1-5]. Late transition metals, mostly the precious mechanisms. Consequently, few literature examples metals, stand as the most versatile catalytic systems for a are found where a thorough mechanistic investigation variety of functionalization reactions demonstrating their have been conducted with strong support either by robustness in several applications in organic synthesis [6- theoretical calculations or experimentation. Therefore, 12]. Owing to the common interest in the catalysts mode we consider of highly scientific interest reviewing the of action by many research groups, nowadays we have a last advances on mechanistic studies on Fe, Co and Mn wide understanding of the mechanistic aspects of precious on C-H functionalization in order to get a deep insight on metal-catalyzed reactions.